Usually I do more online listening than downloading, but lately there
are just tons of albums that I want to have in my iTunes. What do
you guys think is the most solid site for getting albums with the least
risk of screwing up your computer?

But if you don't want to have to install anything, mediafire and other similar sites (though mediafire is the best by far) is the way to go. Just search on google for blogspots, or directly for links and you shouldn't have any problem finding what you're searching for.